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Adeno-associated virus (AAV) vector system has several useful advantages with regard to in vitro and in vivo gene transfer. However, their usages have been limited by cumbersome and labor-intensive vector production in the traditional method. To overcome limitations in AAV production, in this report, we explored the possibility of generating AAV packaging cell line, 293T R/C.VA.E2A.E4. cells, by using lentivirus-mediated transduction of Rep/Cap gene of AAV-2, VA RNA, E2A, and E4 genes of Ad5 into 293T cells. In packaging cell lines, it is important that supply of the AAV vector can be stably performed for long time. We showed that the 293T R/C.VA.E2A.E4. cells have stably maintained the transduced components after more than 10 passages and yielded high-titer AAV vectors, and the titer of AAV vectors did not decline even if culture of the packaging cells was continued for long time. The Rep/Cap and E4 gene products caused no remarkable cytotoxicity. The 293T R/C.VA.E2A.E4. cells might be able to tolerate the Rep/Cap and E4 gene products, or have less copy numbers of the Rep/Cap and E4 genes than the traditional method. Moreover, we showed that the AAV vectors derived from 293T R/C.VA.E2A.E4. cells infected the primary human CD34+ haematopoietic progenitor cells with high efficiency (50-70%). In the 293T R/C.VA.E2A.E4. cells, the AAV vectors can be generated by the transfection of one AAV vector plasmid, and large-scale AAV production can be easily achieved. It is important that cumbersome, variable, and costly transfection is avoided.  相似文献   
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Background: Background: Liver disturbance in rheumatoid diseases results not only from liver disease associated with the rheumatoid diseases themselves but also from various other causes. This study aimed to elucidate the clinical features of liver disturbance in rheumatoid diseases, focusing on the cause of this disturbance. Methods: A clinicopathological study was performed in 306 patients (106 with systemic lupus erythematosus, 71 with Sj?gren's syndrome, 59 with rheumatoid arthritis, 27 with scleroderma, 30 with polymyositis, and 13 with polyarteritis nodosa). Results: Liver disturbance occurred in 43% of these patients and resulted from various causes. Its degree and duration varied from one cause to another. Liver disease associated with rheumatoid diseases was the leading cause of the liver disturbance in these patients and was characterized by mild and transient liver disturbance (maximum alanine aminotransferase [ALT] level during the study period, 68 ± 8 IU/ml; maximum alkaline phosphatase [ALP] level, 410 ± 31 IU/ml; duration of liver disturbance, 6 ± 2 months). Most patients with this type of liver disease showed minimal change in liver histology, although two-thirds of those evaluated by the international scoring system for autoimmune hepatitis (AIH) were classified as “probable” or “definite”. Eight of 14 patients with histologically proven chronic hepatitis or cirrhosis were infected with hepatotropic virus (7 with hepatitis C virus [HCV] and 1 with hepatitis B virus [HBV]). Five of 9 patients in whom the hepatic lesion progressed had hepatotropic virus infection (4 with HCV and 1 with HBV), and the other 4 patients suffered from autoimmune liver diseases. Conclusions: Liver disease associated with rheumatoid diseases was the leading cause of liver disturbance in these patients and was characterized by mild and transient liver disturbance, whereas progressive liver diseases were often associated with hepatotropic virus, mainly HCV, or autoimmune liver diseases. Liver histology is indispensable for differentiating AIH from liver disease associated with rheumatoid diseases. Received: August 27, 2001 / Accepted: January 7, 2002  相似文献   
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The management of LSRS is a crucial problem to ensure a sufficient PV flow during pediatric LT. Although several techniques have been indicated to solve this problem, a more appropriate approach to LSRS is still needed in pediatric LT. We herein present a modified surgical approach to the ligation of LSRS via the left side of the IVC for a nine‐month‐old boy with severe portal hypertension and a history of Kasai portoenterostomy. LSRS was identified and exposed through the left side of the IVC and the dorsal surface of the pancreas from the superior side of the body of the pancreas. The post‐operative course was uneventful with an excellent PV flow. The central approach for the ligation of LSRS is worth considering as an alternative procedure for a patient with collateral vessels and a history of multiple laparotomies.  相似文献   
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BACKGROUND: Brugada syndrome is a form of idiopathic ventricular fibrillation characterized by right bundle-branch block pattern and ST elevation in the right precordial leads of the ECG. The SCN5A gene encodes the alpha-subunit of the human heart sodium channel, which plays a critical role in cardiac excitability, and mutations of SCN5A could underlie Brugada syndrome. METHODS AND RESULTS: To detect mutations of SCN5A, DNA samples from 12 Japanese patients with Brugada syndrome were analyzed using direct sequencing. Two patients had novel mutations, G292S and S835L, but no other mutations of SCN5A were detected in the remaining patients. The first mutation, G292S, was identified adjacent to the pore-lining region between the DIS5 and DIS6 transmembrane segments of SCN5A, and the second mutation, S835L, was in the intracellular loop connecting the DIIS4 to DIIS5. Both mutations were not detected in 100 unrelated control subjects. CONCLUSION: Two novel SCN5A mutations have been found in Japanese patients with Brugada syndrome.  相似文献   
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PC is produced in the liver and inhibits blood coagulation by catalyzing active factors V and VIII. PC deficiency causes abnormal blood clotting that is difficult to regulate by anticoagulative treatments. Four reports of PC deficiency treated with LTx have been published; however, no report of DLT as a therapy for PC deficiency is available. We describe a case of a 23‐month‐old girl who received DLT for compound heterozygous PC deficiency. Her PC activity was below 5%. She developed intracranial lesion and frequent refractory purpura fulminans. Both her parents had heterozygous mutations of PC genes and were excluded as living donors. Furthermore, she was a low priority on the waiting list of deceased‐donor transplantation. We performed living DLT using the liver from a patient with MSUD. Activated PC concentrate safely supported the perioperative period. After DLT, she maintained normal PC activities and BCAA levels. This is the first case of PC deficiency successfully treated by living DLT with MSUD. We propose that DLT using liver from patients with MSUD is a treatment option for PC deficiency.  相似文献   
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